To PDF or Not to PDF? Online Accessibility for People with Disablities
Thursday, 24th March 2011 at 11:51 am
The way information is presented online by governments and others can make it difficult for those with disabilities, according to a new study by the Australian Government.
In particular, the Federal Government study looked into the accessibility of the Portable Document Format, or PDF, for people with a disability.
The report says that information presented online in the PDF format makes it difficult for the ‘assistive’ technology that is available to do what it needs to.
The PDF was first created by Adobe Systems in 1993, and is very widely used for online documents. While it has wide utility, its suitability for accessibility purposes has been criticised.
In 2010, Vision Australia, with the cooperation of Adobe, undertook the study of the Portable Document Format’s accessibility capabilities.
The study’s scope was designed to increase understanding of its strengths and weaknesses.
The study has found that while accessibility of the Portable Document Format is improving, like most tools, it cannot compensate for poor design.
It says content authors need to design accessibility into their documents from the outset.
The report says many technologies have accessibility issues but the Portable Document Format (PDF) is the one most often the subject of web accessibility complaints.
It says people with disabilities face challenges in dealing with the online world. In order to participate in the online world they employ many adaptive strategies and use a range of tools commonly known as assistive technologies. These include text to speech software and screen magnifiers to name a few.
The study showed there are a number of drawbacks in relying on technical evaluations as the sole determinant of accessibility. While technical evaluation might indicate a product is accessible, the user’s experience in whether they can achieve their specified goals with effectiveness, efficiency and satisfaction is the most important measure of accessibility.
Overall, the Study found that there is insufficient evidence to establish that the development of the Portable Document Format and improvements in assistive technologies have advanced enough for PDF files to be considered accessible for people with a disability, particularly for those who are blind or have low vision.
The Study also highlighted that the issues contributing to the inaccessibility of PDF files, when used with assistive technologies, are not in general directly attributable to the Portable Document Format itself.
The issues that result in an inaccessible PDF file are:
- the design of the PDF file by the document author to incorporate the correct presentation, structure, tags and elements that maximise accessibility;
- the technical ability of the assistive technology to interact with the PDF file (via the relevant PDF Reader); and
- the skill of the user and their familiarity with using their assistive technology to interact with a PDF file.
The findings of the Study raise the need for:
- An updated position on the use of PDF files on government websites; including a review of the use of PDF files when the PDF/UA standard is released and Sufficient Techniques become available to satisfy WCAG 2.0 conformance;
- An internationally-agreed position on the characteristics a PDF file must have for optimal accessibility and a transparent indication of the time and skill required to create such files;
- A study into the impact (cost and resource implications) in creating accessible PDF files;
Better resources and tools to support people in the creation of accessible PDF files, including clear and centralised guidance for government agencies on:
- appropriate use of the Portable Document Format;
- how to optimise PDF files for greater accessibility;
- the importance of testing PDF files for accessibility;
Education programs, for authors and publishers of government documents, that include:
- the impact of inaccessible web content on people with a disability;
- information about assistive technologies and how they are used;
- advice on how to author documents for online publication; and
Government agencies to:
- examine their use of PDF documents;
- examine their workflow process in the creation of PDF files;
- continue to offer a choice of file formats.
The full report can be found at http://www.finance.gov.au/publications/pdf-accessibility-study/index.html